Inner core vs no core?

[seann]

Hello, I have been using 3/4" hollow core for years on sewers with no issue.
I have always used a plastic inner core in my 3/8 cables for kitchen sinks and such. However, I am considering switching to no core on 3/8 cables and wondering if it is a bad idea or not?
Have any if you guys used 3/8 no core cables before? And have you had any issues with no core vs inner core on 3/8 cable?

 

[Sylvan]

Small cables are good without an inner core as they are more flexible 1/1/4 -2" drains.

Cables 1/2" - 1.25 inner core I like better as they don't twist so much and are better when encountering roots etc.